Cryogenic (CO2-Dry Ice) Cleaning for Electrical Rotating Machines
Cryogenic Cleaning Method
- Cryogenic cleaning is a process in which particles of solid carbon dioxide are propelled at a high velocity to impact and clean a surface.
- Traditional cleaning methods like bead blasting and sand blasting clean through a chiselling action, much like using an ice pick often damaging the substrate.
- Cryogenic cleaning on the other hand might be compared to a spatula as it lifts the contaminant away.
Illustration of the cleaning:
- The dry ice penetrates below the pollutant and instantly expands because of conversion from the solid to the gaseous state.
- This sublimation creates a wave of compression tension between the contaminant and the substrate.
- The carbon dioxide evaporates relocating the pollutant, which typically falls to the ground.
Traditional Cleaning Methods
- Affects the insulation
- Not environmentally friendly
- Post dry out required
- Abrasive in nature
- Moisture Ingress
- Post Dry out in an oven mandatory
How it works ….
- Step # 1 - Energy Transfer : Dry ice is propelled outside the blasting at high speeds to impact the surface. The force of this impact is the primary means of cleaning.
- Step # 2 - Micro Thermal Shock : The cold temperature of the dry ice hitting the contaminant creates a micro thermal shock at -79 degrees centigrade thereby breaking the bond between the surface contaminant and the substrate.
- Step # 3 - Gas Pressure : Sublimation of the dry ice on impact forces off the contaminant from behind because of expansion form the solid to gaseous state.
- Post dry out not required
- Not abrasive in nature does not damage the substrate
- Ideal for in position cleaning – reduced down time
- Environmentally Friendly
- Provides a cleaner Clean
- Insulation values improve immediately on cleaning
- Non-flammable and nonconductive